The Marina, one of the greatest advantages of Barcelona is that it is a seaside city, how lucky.
The buildings are also stunning, Gaudi's works are my all time favorite.
Walking up Passeig de Gracia street, you can see the Casa Batllo (above pics)
and La Pedrera (below). I love the originality of these buildings.
In this same street there are many luxury shops such as Hermès, Rolex, D&G, Lowe, etc.